Condensation products of alkoxymethylated diaromatic ethers



3,274,157 CONDENSATION PRODUCTS OF ALKOXY METHYLATED DIAROMATIC ETHERS James D. 'Doedens, Midland, Mich assignor to The Dow Chemical Company, Midland, Mich a corporation of Delaware No Drawing. Filed Apr. 1, 19-55, Ser. No. 444,792

'7 Claims. (Cl. 269-47) This application is a continuation-impart of application Serial No. 106,548, filed May 1,1961.

The present invention concerns certain new alxoxymethyl derivatives of diaromatic ethers which are capable of undergoing condensation to provide solid polymerized products. The invention is also concerned with the preparation of such monomeric and polymeric compositions.

It is a principal object of the present invention to provide novel monomeric compositions capable of being polymerized to provide solid resinous products. Afurther object of the invention is to provide novel resinous prod-v United States rea resinous products.

here1n,'means having an average alkoxymethyl functional a 3,274,157 Patented Sept. 20, 1955 methyl functionality are thermoplastic, toluene-soluble,

Essentially mono, as' employed ity of l up to about 1.2. Itis thus apparent that'mixtures having a small proportion of derivatives of higher funcor unfilled, thermoset articles of construction;

wherein Ar is an aromatic radicaLpreferably of the hen-f zene series. It may be nuclearly substituted with up to 2 alkyl, alkoxy and/ or halo groups and have a total of from 6 to 14 carbons. Otherwise in the formula, 11 is an integer from 1 to 4, and R is an alkyl hydrocarbon group con D either aromatic radical. Usually, the alkoxymethyl moieties of the polyfunctional compounds will be distributedbetween the aromatic portions of the ether such that each aromatic radical of the compound will have at least one alkoxymethyl moiety and, when possible, an equal number of such moieties. The terminology alkoxymethylated diaromatic ether composition, as employed herein, includes both individual alkoxymethyl derivatives and mixtures thereof. These compositions can be characterized by an alkoxymethyl functionality number which may range from 1 up to and including 4. The alko'xymethyl functionality is based on the average number of such substituent' groups per diaromatic ether molecule.

The alkoxymethylated diaromatic ether compositions of the invention can be caused to condense to provide solid resinous products when heated at suitable elevated ternperatures in the presence of a condensation catalyst for the reaction. The reaction is accompanied by the splitting out of an alkanol corresponding 'to the protonated alkoxy portion of the above-described alkoxymethyl moiety. Catalysts for the reaction are generally of the class known as Friedel-Crafts catalysts. Useful catalysts include aluminum chloride, ferric chloride, stannic chloride, boron trifiuorlde and zinc chloride, hydrogen fiuor ide, sulfuric acid, phosphorous pentoxide and phosphoric tionality can be utilized to provide thermoplastic resins. Such resinous products are useful as resinous binders and in addition they may be employed to prepare films or fibers which are water insoluble and resistant to the action of alkalies.

i l 1 Those alkoxymethylated diaromatic ethers having from 2'up to and including 4 alkoxymethyl groups per'molecule provide thermoset resinous products. In mixtures, however, an average alkoxymethyl functionality above a minimum of about 1.2 alkoxymethyl groups per molecule is all that is necessary to provide thermoset resins. By

- virtue of this fact, it is apparent that some and, in fact, a i large proportion of monofunctional materials can be employed with those of a higher functionality to produce thermoset resins. Such thermoset resins can be utilized to provide any of a Wide variety of useful molded, filled In addi tion, such resins'are most advantageously adapted, when polymerized by means of mass reaction techniques, to provide solid plastic foams useful as insulation in the construction industry. The alkanol that is split out during the condensation reaction functions as a natural blowing agent at the temperature of the reaction.

To prepare the polymerizable compositions of the invention, a suitable alcohol such as methanol, ethanoL. propanol or butanol is caused to condense with a halomethylated diaromatic ether composition in the presence of an alkali such as, for example, sodium hydroxide or carbonate. The reaction employed is essentially that of the Williamson ether synthesis.

The halomethylated diaromatic ether, compositions utilized in this reaction are known. For example, such compositions can be obtained pursuant to the methods disclosed in United States Letters Patent"2, 9l1,380. Specific halo'me'thylated diaromatic ethers that-are shown therein include mouo(chloromethyl)diphenyl oxide, di- (chloromethy1.)diphenyl oxide, tri(chloromethyl) diphenyl oxide, tetra(chloromethyl) -diphenyl oxide, mono (bromomethyl) diphenyl oxide, di(bromomethyDdiphenyl oxide, tri(bromomethyl)diphenyl oxide, tetra(bromomethyl)diphenyl oxide, momo(chloromethyl) ditolyl oxide, di(chloacid. Other condensation catalysts include such strong protonic acids as hydrochloric, hydrobromic and nitric acids. In a generic sense all such catalysts are Lewis acid having a property of catalyzingcondensation reac tions involving aromatics.

romethyl)ditolyl oxide, tri(chloromethyl)ditolyl oxide, tetra(chloromethyl)ditolyl oxide including all possible isomers and halo-, alkoxyand alkyl-substituted derivatives of the foregoing halomethylated diaromatic ethers,

'the alky-l substituent groups containing from 1 to 4 carbon atoms. The foregoing compounds correspond gen-" '7 er-ally to the following formula:

. aroma- 9+ wherein R is the above-described halo, alkoxy and/ or alkyl group, X is selected from the group.consisting of chlorine and bromine, 'm is a number from '1' i6 4, in-

positions are usually mixtures of isomers and homologs having varying numbers of halomethyl substituents per molecule. While such product mixture can be separated to provide individual compounds which canbe separable utilized in the present invention, the mixtures themselves are good starting-.materials for-the preparation of the mixed alkoxymethyl diaromatic ether compositions of the invention.

In preparing the alkoxymethylated diaromatic ethers of the invention, a preferred mode of operation involves adding an effective amount of an alkali hydroxide to a mixture of the etherifying alcohol and the halomethylated diaromatic ether. The resulting mixture is I a heated at an elevated temperature of at least about 60 C. under autogenous pressures. Higher temperatures up to 170 C. can be employed and when the mixture is. above its boiling point, the reaction is carried out in a pressurized system. A most convenient reaction tempera- -ture is the reflux temperature of the mixture. The minimum amount of alkali employed should be at least halogen is about 1.05:1.00.

As the alkali hydroxide is added to the alcohol-halomethylated diaromaticether mixture, an exothermic reaction occurs which is sufliciently pronounced that care should be exercised to avoid adding the alkali tdo rapidly. At least enough alcohol is employed to react stoichiometrically with each available halomethyl group in the halomethylated diaromatic ether composition. at least about 3 up to about moles of the alkanol are employed for each chemical equivalent of halomethyl groups present. Larger amounts can be employed but it is generally uneconomical to do so.

zone feed streams may utilize comparatively short contact times for efi'ective operation.

'Upon achieving a desired degree of conversion of the reactants to the desired product, the reaction mass may be filtered to remove any alkali halides that are formed during the reaction. Subsequently, the filterate is heated under reduced pressures to distill olf any unreacted alkanol or other volatiles that may be present. The product thus recovered consists essentially of the desired alkoxymethylated diaromatic ether.

The alkoxymethylated diaromatic ethers of the invention can be polymerized or condensed at temperatures above about 60 C. and inthe presence of Lewis acid condensation catalysts especially Friedel-Crafts catalysts, to provide solid resins. The desired polymerization reaction is evidenced by the formation and evolu- 4 best for the preparation of foamed solid, resinous prod ucts. tures, up to the decomposition temperatures of the polymerizable composition and resinous products thereof, can be employed.

The amount-of catalyst required to initiate the condensation reaction will vary according to the temperature employed. At lower temperatures, e.g., about 70 C., as much as 2 to'5 percent or more of the catalyst may be required based on the weight of the resin-forming alkoxymethylated diaromatic ether. e.g., about 160-200 C., lesser amounts of catalyst,e.g., about 0.1 to 1 percent by weight of the polymerizable composition, can be employed.

The reaction .for the formation of the solid resins is usually conducted at atmospheric pressure or thereabouts,

I but it also can be accomplished at higher or lower pressures. At atmospheric pressures and lower, the mass re- .action products of the thermosettable compositions are normally solid foam products. Under substantially greater pressures such as those obtained in compression molding machines, the resinous products can be compressed into essentially dense non-foamed bodies.

Solid resinous products of the invention that are prepared with phosphoric 'acid as the catalyst are self-extinguishing. When exposed to a flame that is subsequent- Preferably, a

ly withdrawn, any burning of such resinous products ceases within 2 seconds after removal of the flame source;

The resin-forming compositions of the invention can be most efiicaciously applied to an inert filler substrate as the dispersed phase in a. suitable solvent medium. 'For example, the alkoxymethylated diaromatic ether composition can be dispersed or emulsified in water, or dissolved in a relatively non-polar organic solvent such as xylene and in such forms be sprayed, poured or otherwise incorporated into or onto a suitable filler. The excess liquid is permitted to drain off and the dispersing solvent removed by evaporation. The latter operation may be aided by the employment of temperatures below those at which the alkoxymethylated diaryl ether undergoes condensation. Sufficient quantities of the resin-forming composition are thus incorporated into the filler to provide anywhere from about 1 to about 80 percent by weight. of the ether based on the weight of the total composition. Usually, an effective quantity of a suitable catalyst is intion. Another method of catalyst application involvesincorporating the catalyst into the resin-forming composi tions of a lower alkanol corresponding to the protonated gardless of the size of the alkyl group, temperatures above about 165 C. are suflicient to cause the condensation reaction to occur. Preferably, the reaction is carried out whenever possible within the temperature range from ;1 75

about 1'30 to about 180? C. which temperature range tion filler combination in a separate step prior to curing the combination. The catalyzed, coated filler mass is shaped into a desired form and cured to a thermoset form by heating it at an elevated temperature above about 60 C. for a period of time anywhere from about-5 seconds to several minutes depending upon the particular temperature employed and thickness of the body to be cured and the like considerations affecting heat transfer.

Particular inert fillers that can be employed inconjunction with the resin-providing ethers of the invention include various inert filler substances such as, for example,

siliceous fillers which include sand an d glass fibers and t I carbonaceous fillers which include graphite, coke breeze, powdered coal and the like, fillers. Othersuitable fillers include mineral and synthetic fibers, asbestos, .flyash,

blast furnace and powerhouse slags, mica flour, wood flour, wood particles and the like fibrous or granular substances'that are substantially inert to the resin-providing ethers of the invention and which do not melt, fuse excessively or decompose at or below temperatures required to cure or condense the ether binders coated thereon.

The following examples illustrate the present invention 7 but are not to be construed as limiting.

EXAMPLE 1 A 1I uer flask equipped with a stirrer, thermometer If desired, however, substantially higher tempera-.

At higher temperatures, 7

andjreflux condenser was charged with about 250 cc. of

methanol and about 40 grams of sodium hydroxide. The resulting composition was heated to about 65 C. whereupon it.started to reflux. At this point, 133 grams of parachloromethyl diphenyl oxide was added dropwise with stirring. Thereafter, the reaction mass was mainvtained at its reflux temperature for about 4 hours and I 7 then allowed to cool. The reaction product was filtered to remove sodium chloride, which solids were washed Toluene and residual alkanol in the organic product thus recovered were distilled ed at about 160 C. under re- Ultimately, 116.5 grams of a product duced pressure. were obtained having a refractive index, 12 of 1.5638. This product was distilled and the fraction collected at about 105 C. under an absolute pressure of 0.25 millimeter of mercury and weighed 105 grams. The distillate exhibited a refractive index, n of 1.5642. A portion of the purified product was subjected to chemical analys'is for carbon and hydrogen. Also, an infrared absorption spectrum was obtained for the purified product. The product was found to contain 78.45 percent carbon and 6.66 percent hydrogen, which figures compare to theoretical amounts of 78.48 percent carbon and 6.59 percent -hydrogen for monomethoxymethyl diphenyl oxide.

Moreover, the infrared spectrum confirmed the structure of the resulting product as para-methoxymethyl diphenyl oxide.

To 15 grams of the monomethoxymethyl' diphenyl oxide in a small beaker was added about 5 drops of phosphoric acid with agitation. The resulting mixture was then heated on a hot plate up to a temperature of about 190 C. at which point the mixture clouded up and methanol began to evolve. Thereafter, the temdenser, stirrer and dropping funnel was added 400 grams of methanol and 198 grams of 85 percent potassium .hydroxide.- The resulting mixture was heated to its reflux temperature and a solution of 401 grams of 4,4- di(chloromethyl )diphenyl oxide in 272 grams of methanol was added dropwise to the methanol-alkali solution.

During the course of the addition of the chlorornethylated diaromatic ether, the reaction mass was maintained at its reflux temperature as a 'result of the exothermic nature of the reaction. After the addition of the ether was complete, the reaction mixture was maintained at its reflux temperature for about 3 hours in orderto insure substantial conversion of the reactants to the desired product. 'The reaction mixture was then cooled and potassium chloride separated therefrom by filtration. was heated under a vacuum to remove unreacted methanol and the residual product distilled in a 6 inch Vigreux perature of the reaction mass rose to 201 C. Subsequently, the temperature of the reaction mass was increased to about 270 C. Over the higher temperature range, the viscosity of the reaction mass increased and its color changed from an essentially clear mass to light yellow. When cooled, the reaction mass became a hard, yellow solid. The molecular-weight of the resulting polymer, as determined by thehboiling point elevation technique in a modified Menzies-Wright ebulliometer, was about 1650.

The course of the polymerization reaction can be followed by the technique of drawingsmall portions of the reaction mass into fibers. The extent or degree of'reaction is directly proportional to the length of a fiber that can be drawn from the reaction mass.

EXAMPLE 2 column under reduced pressure. The fraction collected boiled at about 143 C. under an absolute pressure of 0.3 millimeter of mercury. Based on the starting material, the yield of 4,4'-di(methoxymethyl)diphenyl oxide thus obtained was 62.5 percent. It was a water-clear liquid having a refractive index, 11 of 1.5543.

In a manner similar to that above, other compositions of the invention were prepared by substituting other alcohols such as ethanol, propanol and butanol'for-the 'methanol to provide the corresponding 4,4'-di(alltoxymethyl)diphenyl oxide products. The refractive index and boiling points at reduced pressures of these products are set forth in the following Table 1.

Mixed reaction products obtained by chloromethylating of diphenyl oxide were etherified withmethanol, ethanol, propanol and butanol in the presence of caustic according to the procedure employed in Example 2. The compositions of the mixed chloromethylated diaromatic others that were employed are set forth in the following Table 2. A convenient designation of a particular reaction product To a three liter glass flask equipped with a reflux conmixture 15 the weight of chlorine 1n that mixture.

Table 2 Halomethylated Diuromatic Ether Compositions Classified According to Chlorine Content 17.6% C1 26.7% CI 25.2% C1 31.7% C1 (CMDPO-l?) (CMDPO-23) (CMDPO-25) (CMDPO-32) Component, Mole Per- 7 cent: Diphenyl ether O) 17. 3 0. 0 0. 0 0. 0 o-Monochloromethyl.

5.3 0.5 0.25 0. 0 p-Monochloromethyl 42.9 4.7 2.35 0.04 I o,p'-Dichloromethyl D 10.8 35.5 17.7 1.9

P,D'-Dich1orornethyl 3 DYO 20.6 37.7 69.5 8.6 Trichlorornethyl DPO; 2.3 21.1 t 10.5 89.0

. Tetmchloromethyl .DPo 0.5-1.0 0. 5-1.0 0.5

The mixed alkoxymethylated products thus obtained are set forth in the following Table 3 along with their re fractive index, density and color properties.

. 8 wherein R is selected from ethyl, propyl and butyl radicals, R is selected from the group consisting of .al!-:yl, alkoxy and halogen radicals T able 3 Mixed Aiken-methyl Chloro j Comp. methylated mm (153 DPOcursor Methoxymethyl DPO CP-lDPO-IT Ethoxymethyl DPO. l. 1. ET-3 Propoxymethyl DPO I i. 1. L Butoxyniethyl DPO I l. 1. L Methoxymethyl i) For I 1. 1. 1 LC. yellow. Ethoxymethyl DPO 1. 1.078 DJ.

' Propoxyme thyl D PO... 1. 1. 054 Yellow. Butoxymethyl DPO 1. 1. 033 bled. yellow. Methoxy'methyl DPO--. l. 1, 110 Very It. yellow. Ethoxymethyl DPO 1. 1. G9 D0. Property-methyl DPO 1. a l. 046 1 ellow. Butoxymethyl DPO. 1. 52 1. 028 Do. Methoxymethyl DPO '1. 1. 112 Lt. yellow. Ethoxymethyl D PO 1. 1. 06% Med. yellow.

Propoxymethyl DPO C.\lDPO32 1. 5277 1. 040 Cloudy amber.

........ Butoxymethyl DPO CMDPO-SL" 1. 5210 1. 016 Dark yellow.

, EXAMPLE 4 The alkoxymethylated diph'enyl oxides prepared in the above examples wherein the alltyl group is methyl, ethyl, V propyl or butyl, which compounds have an average alkoxymethyl functionality per molecule of at least 1.2, are mixed with about /2 percent by weight of ferric chloride based on the weight ofthe polymerizable composition. The liquid catalyzed compositionis then applied directly to a wgven fiberglass substrate and the resulting coated article molded simultaneously with the application of heat above about 200 C. to provide a solid thermoset shaped article having excellent resistance to the action of alkalies.

Results similar to that ofthe foregoing are achieved when another catalyst for the reaction such as zinc chloride, boron trifiuonde, stannic chloride, stannouscbloride,

antimony chloride, phosphorus pentoxide or sulfuric acid is substituted for the phosphoric acid of Examples 1-3 and the ferric chloride of Example 4.

What is claimed is: 1. A solid polymerized composition of matter obtained by heating, in the presence of a condensation catalyst, an alkoxymethylated diaryl ether having the general formula:

ROCHzwhereinR is selected from the group consisting of methyl, ethyl, propyl and butyl radicals, R is selected from the wherein the alkyl group contains from 1 to 4 carbon atoms, n; is a number from 1 to 4 representing an average alkoxymethyl functionality and n is an integer from 0 to 2.

2. A solid polymerized composition of matter obtained by heating at a. temperature above about 60 C. in the presence of a. Friedel-Crafts catalyst the composition of matter having the general formula:

wherein the alkyl group contains from 1 to 4carb'on' 7 atoms, In is a number from 1 to 4 and n is an integer from group consisting of alkyl, alkoxy and halogen .radi'cals 3. A solid polymerized composition of matter obtained by heating an alkoxymethyl diphenyl oxide composition having an average of from 1 to 4 alkoxy-methyl groups per molecule, the alkyl moiety containing from 1.- to 4 carbon atoms, above about 60 C. in the presence .of a Friedel-Crafts catalyst.

4. A'solid thermoset composition of matter obtained by heating an alkoxymethyl diphenyl oxide composition having an average of from about 1.2 up to 4 alkoxymeth'yl groups per molecule, the alkyl moiety containing from 1 to 4 carbon atoms, above about 60 C. in the presence of a Friedel-Crafts catalyst. 5. A thermoset product comprising an inert filler and the composition of claim 4.

6. A fiber'comprising a condensation polymerization product of an alkoxymethyl diphenyl oxide composition having an average of from about 1 to about 1.2 alkoxymethyl groups per molecule, the alkyl moiety having from 1 to 4 carbon atoms.

7. A method for polymerizing alkoxymethylatetl diaryl I ether,,which method comprisesheating said composition at a temperature-above about 60 C. in the presence of a Lewis acid condensation catalyst, said alkoxymethylated diaryl ether having the general tormula:

wherein R is selected from the group consisting of methyl, ethyl, propyl and butyl radicals, R is selected from the group consisting of alkyl, alkoxy and halogen radicals wherein the alkyl group contains from 1 to 4 carbon atoms, m is a number from 1 to 4 representing an average alkoxymethyl functionality and n is an integer fromO to 2.

References Cited by the Examiner i WILLIAM H. SHORT, PrimoryExaminer i I; c; MARTIN, A a Examiner.

the group consisting of methyl, 

1. A SOLID POLYMERIZED COMPOSITION OF MATTER OBTAINED BY HEATING, IN THE PRESENCE OF A CONDENSATION CATALYST, AN ALKOXYMETHYLATED DIARYL ETHER HAVING THE GENERAL FORMULA: (((R'')N-PHENYL)-O-),(R-O-CH2-)M-BENZENE WHEREIN R IS SELECTED FROM THE GROUP CONSISTING OF METHYL, ETHYL, PROPYL AND BUTYL RADICALS, R'' IS SELECTED FROM THE GROUP CONSISTING OF ALKYL, ALKOXY AND HALOGEN RADICALS WHEREIN THE ALKYL GROUP CONTAINS FROM 1 TO 4 CARBON ATOMS, M IS A NUMBER FROM 1 TO 4 REPRESENTING AN AVERAGE ALKOXYMETHYL FUNCTIONALITY AND N IS AN INTEGER FROM 0 TO
 2. 